SIRET number
What is a SIRET number?
A SIRET number is a 14-digit code that identifies one physical location of a registered business in France. It combines the company's 9-digit national registration number with a 5-digit code for that specific address, so a business with several branches holds a separate SIRET for each one.
Key facts
- Issued by INSEE, the French national statistics institute, when a business registers or opens a new location.
- 14 digits total: the first 9 form the company-wide registration number, the last 5 identify the individual establishment.
- Every physical location gets its own SIRET, even when it belongs to the same legal entity.
- Appears on French invoices, contracts, and the KBIS registration extract.
- Distinct from a , which a payment processor assigns internally rather than a government registry.
How it works
The leading 9 digits stay fixed for the company wherever it operates. The trailing 5 digits change per address: 4 identify the establishment in registration order, and a final check digit validates the full 14-digit sequence with the Luhn algorithm. When a French merchant opens a second office, INSEE issues a new SIRET that keeps the same leading block and adds a different establishment code.
SIRET vs SIREN
SIRET and SIREN are often used interchangeably, but they aren't the same identifier.
| SIRET | SIREN | |
| Length | 14 digits | 9 digits |
| Identifies | One physical location | The legal company as a whole |
| Changes per branch | Yes - each location gets its own | No - shared across every location |
Why it matters
Payment processors and acquirers ask French merchants for a SIRET number during checks because it links the application to a verifiable public registration record. A SIRET that doesn't match the merchant's legal name or address on file flags the application for manual review before the can go live.
